Question 12750
In your first problem, you need to review how to add complex numbers. The real parts are added and the imaginary parts are added. That's it.
I am guessing the second problem is {{{(-2+6i)^2}}}
That just means {{{(-2+6i)(-2+6i)}}}
I get {{{4-12i-12i+6i^2=4-24i-6=-2-24i}}}
Do you agree?